A terrorist bomb "more likely than not" caused a Russian airliner to crash over Egypt, killing all 224 people on board, British Prime Minister David Cameron said.

U.S. and UK intelligence sources agree that it was probably a terror act, although Russian and Egyptian officials refused to acknowledge the possibility.

A video posted soon after the October 31, 2015, air disaster purported to show the Airbus 320 exploding and plunging to earth, although Lead Stories has been unable to verify its authenticity.

CNN quoted unidentified U.S. intel sources saying that intelligence suggests that ISIS or its affiliates planted a bomb on the Russian plane. The flight was heading from Sharm el-Sheikh to St. Petersburg, Russia.

An ISIS affiliate fighting the Egyptian government claimed responsibility for downing the jet in the hours after the crash.

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